SARS-CoV-2 virus transfers to skin through contact with contaminated solids.

Transfer of SARS-CoV-2 from solids to fingers is one step in infection via contaminated solids, and the possibility of infection from this route has driven calls for increased frequency of handwashing during the COVID-19 pandemic. To analyze this route of infection, we measured the percentage of SARS-CoV-2 that was transferred from a solid to an artificial finger. A droplet of SARS-CoV-2 suspension (1 µL) was placed on a solid, and then artificial skin was briefly pressed against the solid with a light force (3 N). Transfer from a variety of solids was detected, and transfer from the non-porous solids, glass, stainless steel, and Teflon, was substantial when the droplet was still wet. The viral titer for the finger was 13-16% or 0.8-0.9 log less than for the input droplet. Transfer still occurred after the droplet evaporated, but was smaller, 3-9%. We found a lower level of transfer from porous solids but did not find a significant effect of solid wettability for non-porous solids.

Interaction between SARS-CoV-2 spike glycoprotein and human skin models: a molecular dynamics study.

The possibility of contamination of human skin by infectious virions plays an important role in indirect transmission of respiratory viruses but little is known about the fundamental physico-chemical aspects of the virus-skin interactions. In the case of coronaviruses, the interaction with surfaces (including the skin surface) is mediated by their large glycoprotein spikes that protrude from (and cover) the viral envelope. Here, we perform all atomic simulations between the SARS-CoV-2 spike glycoprotein and human skin models. We consider an "oily" skin covered by sebum and a "clean" skin exposing the stratum corneum. The simulations show that the spike tries to maximize the contacts with stratum corneum lipids, particularly ceramides, with substantial hydrogen bonding. In the case of "oily" skin, the spike is able to retain its structure, orientation and hydration over sebum with little interaction with sebum components. Comparison of these results with our previous simulations of the interaction of SARS-CoV-2 spike with hydrophilic and hydrophobic solid surfaces, suggests that the "soft" or "hard" nature of the surface plays an essential role in the interaction of the spike protein with materials.

Transcriptomic analysis revealed increased expression of genes involved in keratinization in the tears of COVID-19 patients.

Recent studies have focused their attention on conjunctivitis as one of the symptoms of coronavirus disease 2019 (COVID-19). Therefore, tear samples were taken from COVID-19 patients and the presence of SARS-CoV-2 was evidenced using Real Time reverse transcription polymerase chain reaction. The main aim of this study was to analyze mRNA expression in the tears of patients with COVID-19 compared with healthy subjects using Next Generation Sequencing (NGS). The functional evaluation of the transcriptome highlighted 25 genes that differ statistically between healthy individuals and patients affected by COVID-19. In particular, the NGS analysis identified the presence of several genes involved in B cell signaling and keratinization. In particular, the genes involved in B cell signaling were downregulated in the tears of COVID-19 patients, while those involved in keratinization were upregulated. The results indicated that SARS-CoV-2 may induce a process of ocular keratinization and a defective B cell response.

Identification, Mechanism, and Treatment of Skin Lesions in COVID-19: A Review.

Coronavirus disease 2019 (COVID-19) is a multisystem disease caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), that primarily causes respiratory symptoms. However, an increasing number of cutaneous manifestations associated with this disease have been reported. The aim of this study is to analyze the scientific literature on cutaneous manifestations associated with SARS-CoV-2 by means of a narrative literature review until June 2021. The search was conducted in the following electronic databases: Medline (PubMed), SciELO, and Cochrane Library Plus. The most common cutaneous manifestations in patients with COVID-19 are vesicular eruptions, petechial/purpuric rashes, acral lesions, liveoid lesions, urticarial rash, and maculopapular-erythematous rash. These manifestations may be the first presenting symptoms of SARS-CoV-2 infection, as is the case with acral lesions, vesicular eruptions, and urticaria. In relation to severity, the presence of liveoid lesions may be associated with a more severe course of the disease. Treatment used for dermatological lesions includes therapy with anticoagulants, corticosteroids, and antihistamines. Knowledge of the dermatologic manifestations associated with SARS-CoV-2 contributes to the diagnosis of COVID-19 in patients with skin lesions associated with respiratory symptoms or in asymptomatic patients. In addition, understanding the dermatologic lesions associated with COVID-19 could be useful to establish a personalized care plan.

Do Dogs and Cats Passively Carry SARS-CoV-2 on Hair and Pads?

The epidemiological role of domestic animals in the spread and transmission of SARS-CoV-2 to humans has been investigated in recent reports, but some aspects need to be further clarified. To date, only in rare cases have dogs and cats living with COVID-19 patients been found to harbour SARS-CoV-2, with no evidence of pet-to-human transmission. The aim of the present study was to verify whether dogs and cats act as passive mechanical carriers of SARS-CoV-2 when they live in close contact with COVID-19 patients. Cutaneous and interdigital swabs collected from 48 dogs and 15 cats owned by COVID-19 patients were tested for SARS-CoV-2 by qRT-PCR. The time elapsed between owner swab positivity and sample collection from pets ranged from 1 to 72 days, with a median time of 23 days for dogs and 39 days for cats. All samples tested negative, suggesting that pets do not passively carry SARS-CoV-2 on their hair and pads, and thus they likely do not play an important role in the virus transmission to humans. This data may contribute to confirming that the direct contact with the hair and pads of pets does not represent a route for the transmission of SARS-CoV-2.

Patient Recovery from COVID-19 Infections: Follow-Up of Hair, Nail, and Cutaneous Manifestations.

BACKGROUND: COVID-19 is a pandemic disease worldwide. Although cutaneous manifestations may present in affected patients, there have been limited studies on the cutaneous findings and hair and nail abnormalities after discharge. OBJECTIVE: To establish the cutaneous manifestations, hair and scalp disorders, and nail abnormalities in patients who recovered from COVID-19 infections. METHODS: A retrospective chart review and telephone interviews were conducted to determine the cutaneous manifestations, hair and scalp disorders, and nail abnormalities of patients aged over 18 years who were diagnosed with COVID-19 infections at Siriraj Hospital, Bangkok, Thailand, between January and June 2020. RESULTS: Ninety-three patients with prior COVID-19 infections participated in the study. The COVID-19 severity had been mild for most (71%). Cutaneous manifestations were reported in 8 patients (8.6%), with the common skin conditions being maculopapular rash and urticaria. The onsets of the skin conditions were before admission (1%), during admission (4.3%), and after discharge (3.2%). Increased hair shedding was also reported in 22 patients (23.7%), with a female predominance. Three patients were affected during admission, while the others were affected after discharge. The patients with moderate, severe, and critical COVID-19 infections experienced significantly more hair shedding than those with asymptomatic and mild diseases. Only 2 patients with mild COVID-19 disease reported nail abnormalities (chromonychia and brittle nails). CONCLUSIONS: Cutaneous manifestations, hair disorders, and nail abnormalities can occur in patients with COVID-19 after their discharge from hospital. Patients should therefore be followed up in anticipation of dermatological problems.

Coronavirus (COVID-19) Infection-Induced Chilblains: A Brisk Perieccrine Inflammatory Response.

ABSTRACT: The varying cutaneous and pathological manifestations of coronavirus 2 (SARS-CoV-2 or COVID-19) may have prognostic implications. Acral ischemic findings present with a hypercoagulable state in critically ill COVID-19 patients. Pathologically confirmed varicella-like exanthem and perniosis COVID-19 cases have correlated with paucisymptomatic and asymptomatic patients in previous reports. We present the second case of biopsy-proven COVID-19 infection-induced chilblains (pernio) in a paucisymptomatic patient with a brisk perieccrine lymphocytic response. Based on an antecedent pathological study, we know coronavirus particles have been seen in the eccrine gland associated with a brisk peri-inflammatory response. The prominent perieccrine inflammation is helpful in the diagnosis of COVID-19 infections. Currently, nonischemic pathological findings correlate with a good prognosis based on the paucisymptomatic or asymptomatic nature of their disease courses. Patients presenting with suspected COVID-19 infection-induced chilblains who are paucisymptomatic or asymptomatic should be isolated and immediately tested with polymerase chain reaction (PCR) testing (as there is a delay in diagnosis based on the poor sensitivity of the current rapid test). We continue to stress the importance of early diagnosis and quarantining to prevent spread to the older and immunocompromised patients.

SARS-CoV-2 and Skin: The Pathologist's Point of View.

The SARS-CoV-2 pandemic has dramatically changed our lives and habits. In just a few months, the most advanced and efficient health systems in the world have been overwhelmed by an infectious disease that has caused 3.26 million deaths and more than 156 million cases worldwide. Although the lung is the most frequently affected organ, the skin has also resulted in being a target body district, so much so as to suggest it may be a real "sentinel" of COVID-19 disease. Here we present 17 cases of skin manifestations studied and analyzed in recent months in our Department; immunohistochemical investigations were carried out on samples for the S1 spike-protein of SARS-CoV-2, as well as electron microscopy investigations showing evidence of virions within the constituent cells of the eccrine sweat glands and the endothelium of small blood vessels. Finally, we conduct a brief review of the COVID-related skin manifestations, confirmed by immunohistochemistry and/or electron microscopy, described in the literature.

[Histopathological features due to the SARS-CoV-2]. / Les lésions histologiques associées à l'infection par le SARS-CoV-2.

The infection due to the SARS-CoV-2 leads lesions mainly observed at the respiratory tract level, but not exclusively. The analyses of these lesions benefited from different autopsy studies. Thus, these lesions were observed in different organs, tissues and cells. These observations allowed us to rapidly improve the knowledge of the pathophysiological mechanisms associated with this emergent infectious disease. The virus can be detected in formalin fixed paraffin embedded tissues using immunohistochemistry, in situ hybridization, molecular biology and/or electron microscopy approaches. However, many uncertainties are still present concerning the direct role of the SARS-CoV-2 on the different lesions observed in different organs, outside the lung, such as the heart, the brain, the liver, the gastrointestinal tract, the kidney and the skin. In this context, it is pivotal to keep going to increase the different tissue and cellular studies in the COVID-19 positive patients aiming to better understanding the consequences of this new infectious disease, notably considering different epidemiological and co-morbidities associated factors. This could participate to the development of new therapeutic strategies too. The purpose of this review is to describe the main histological and cellular lesions associated with the infection due to the SARS-CoV-2.

Disinfectant effectiveness against SARS-CoV-2 and influenza viruses present on human skin: model-based evaluation.

OBJECTIVES: Disinfection effectiveness against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on human skin remains unclear because of the hazards of viral exposure. An evaluation model, which has been previously generated using human skin obtained from forensic autopsy samples, accurately mimics in vivo skin conditions for evaluating the effectiveness of disinfection against the virus. Using this model, we evaluated disinfection effectiveness against viruses on human skin. METHODS: Ethanol (EA), isopropanol (IPA), chlorhexidine gluconate (CHG) and benzalkonium chloride (BAC) were used as target disinfectants. First, disinfectant effectiveness against SARS-CoV-2 and influenza A virus (IAV) was evaluated in vitro. Disinfectant effectiveness against SARS-CoV-2 and IAV on human skin was then evaluated by titrating viruses present on the skin after applying each disinfectant on the skin for 5-60 seconds. RESULTS: Both, SARS-CoV-2 and IAV on human skin were completely inactivated within 5 seconds by 40%-80% EA and 70% IPA (log reduction values (LRVs) were >4). However, SARS-CoV-2 and IAV were barely inactivated by 20% EA (LRVs were <1). In vitro evaluation showed that, compared with EA and IPA, CHG and BAC were significantly inferior in terms of disinfection effectiveness. Conversely, the disinfection effectiveness of CHG and BAC against SARS-CoV-2 was higher on human skin than in vitro, and increased with increases in their concentration and reaction time (LRVs of 0.2% CHG/0.05% BAC were >2, and LRVs of 1.0% CHG/0.2% BAC were >2.5). CONCLUSIONS: Proper hand hygiene practices using alcohol-based disinfectants such as EA/IPA effectively inactivate SARS-CoV-2 and IAV on human skin.

SARS-CoV-2 decontamination of skin with disinfectants active during and after application.

BACKGROUND: The coronavirus disease 2019 pandemic has resulted in high levels of exposure of medical workers to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Hand decontamination is one of the actions recommended to reduce the risk of infection. AIM: Two disinfectants - BIAKOS antimicrobial skin and wound cleanser (AWC) and AWC2 (Sanara MedTech, Fort Worth, TX, USA) - were tested to determine whether they can inactivate SARS-CoV-2 upon contact or as a coating applied before contact with the virus. METHODS: The ability of AWC and AWC2 to inactivate SARS-CoV-2 was tested in liquid and dried form on plastic surfaces and porcine skin. FINDINGS: AWC and AWC2 were effective in reducing the infectious titre of SARS-CoV-2 in liquid form during application and in dried form 4 h after application. Virus on skin was reduced up to 2 log10-fold and 3.5 log10-fold after treatment with AWC and AWC2, respectively. CONCLUSION: Application of AWC and AWC2 to skin reduces the level of SARS-CoV-2 and the risk of infection.

From SARS-CoV-2 hematogenous spreading to endothelial dysfunction: clinical-histopathological study of cutaneous signs of COVID-19.

BACKGROUND: To date, very few studies on clinical-histopathological correlations of cutaneous disorders associated with COVID-19 have been conducted. CASE PRESENTATION: The Case 1 was a 90-year-old man, who tested positive for SARS-CoV-2 from a nasopharyngeal swab. Two days later, he was hospitalized and after eleven days transferred to Intensive Care Unit. A chest CT showed bilateral ground-glass opacities. Just that day, an erythematous maculo-papular rash appeared on trunk, shoulders and neck, becoming purpuric after few days. Histological evaluations revealed a chronic superficial dermatitis with purpuric aspects. The superficial and papillary dermis appeared edematous, with a perivascular lympho-granulocytic infiltrate and erythrocytic extravasation. At intraepithelial level, spongiosis and a granulocyte infiltrate were detected. Arterioles, capillaries and post-capillary venules showed endothelial swelling and appeared ectatic. The patient was treated with hydroxychloroquine, azithromycin, lopinavir-ritonavir and tocilizumab. Regrettably, due to severe lung impairment, he died. The Case 2 was a 85-year-old man, admitted to Intensive Care Unit, where he was intubated. He had tested positive for SARS-CoV-2 from a nasopharyngeal swab two days before. A chest RX showed bilateral atypical pneumonia. After seven days, a cutaneous reddening involving trunk, upper limbs, neck and face developed, configuring a sub-erythroderma. Histological evaluations displayed edema in the papillary and superficial reticular dermis, and a perivascular lymphocytic infiltrate in the superficial dermis. The patient was treated with hydroxychloroquine, azithromycin, lopinavir-ritonavir and tocilizumab. Sub-erythroderma as well as respiratory symptoms gradually improved until healing. CONCLUSIONS: The endothelial swelling detected in the Case 1 could be a morphological expression of SARS-CoV-2-induced endothelial dysfunction. We hypothesize that cutaneous damage could be initiated by endothelial dysfunction, caused by SARS-CoV-2 infection of endothelial cells or induced by immune system activation. The disruption of endothelial integrity could enhance microvascular permeability, extravasation of inflammatory cells and cytokines, with cutaneous injury. The Case 2 developed a sub-erythroderma associated with COVID-19, and a non-specific chronic dermatitis was detected at histological level. We speculate that a purpuric rash could represent the cutaneous sign of a more severe coagulopathy, as highlighted histologically by vascular abnormalities, while a sub-erythroderma could be expression of viral hematogenous spreading, inducing a non-specific chronic dermatitis.

SARS-CoV-2 endothelial infection causes COVID-19 chilblains: histopathological, immunohistochemical and ultrastructural study of seven paediatric cases.

BACKGROUND: Chilblains ('COVID toes') are being seen with increasing frequency in children and young adults during the COVID-19 pandemic. Detailed histopathological descriptions of COVID-19 chilblains have not been reported, and causality of SARS-CoV-2 has not yet been established. OBJECTIVES: To describe the histopathological features of COVID-19 chilblains and to explore the presence of SARS-CoV-2 in the tissue. METHODS: We examined skin biopsies from seven paediatric patients presenting with chilblains during the COVID-19 pandemic. Immunohistochemistry for SARS-CoV-2 was performed in all cases and electron microscopy in one. RESULTS: Histopathology showed variable degrees of lymphocytic vasculitis ranging from endothelial swelling and endotheliitis to fibrinoid necrosis and thrombosis. Purpura, superficial and deep perivascular lymphocytic inflammation with perieccrine accentuation, oedema, and mild vacuolar interface damage were also seen. SARS-CoV-2 immunohistochemistry was positive in endothelial cells and epithelial cells of eccrine glands. Coronavirus particles were found in the cytoplasm of endothelial cells on electron microscopy. CONCLUSIONS: Although the clinical and histopathological features were similar to other forms of chilblains, the presence of viral particles in the endothelium and the histological evidence of vascular damage support a causal relation of the lesions with SARS-CoV-2. Endothelial damage induced by the virus could be the key mechanism in the pathogenesis of COVID-19 chilblains and perhaps also in a group of patients severely affected by COVID-19 presenting with features of microangiopathic damage. What is already known about this topic? Despite the high number of cases of chilblains seen during the COVID-19 pandemic, a definite causative role for SARS-CoV-2 has not yet been proven. Different pathogenetic hypotheses have been proposed, including coagulation anomalies, interferon release and external factors. What does this study add? The demonstration of SARS-CoV-2 in endothelial cells of skin biopsies by immunohistochemistry and electron microscopy confirms that these lesions are part of the spectrum of COVID-19. Virus-induced vascular damage and secondary ischaemia could explain the pathophysiology of COVID-19 chilblains. Our findings support the hypothesis that widespread endothelial infection by SARS-CoV-2 could have a pathogenetic role in the severe forms of COVID-19. Linked Comment: Wetter. Br J Dermatol 2020; 183:611.

Cutaneous manifestations in patients with coronavirus disease 2019: clinical and histological findings.

The clinical spectrum of coronavirus disease 2019 is getting wider with the exponential increase of patients worldwide. Initially described with flu-like symptoms, variable cutaneous manifestations have been reported, with only few histopathological descriptions. Detection of the virus in cutaneous samples has been assessed in very few cases until now, and the causative role of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has not been proven for every type of cutaneous manifestations yet. We aimed to describe histological features of cutaneous eruptions occurring concomitantly to SARS-CoV-2 infection and assess by immunochemistry and in situ hybridization using RNAscope validation techniques the presence of the virus in skin lesions. We retrieved all skin biopsies received in the departments of pathology and dermatopathology, University Hospital of Strasbourg, performed in hospitalized SARS-CoV-2-infected patients presenting concomitant cutaneous manifestations since March 2020. In situ hybridization and immunostaining using a polyclonal SARS nucleocapsid protein antibody were performed on each sample. Skin biopsies from six patients presenting morbilliform eruption concomitant to SARS-CoV-2 infection were available for evaluation. All six samples showed varying degrees of spongiosis, perivascular inflammatory infiltrates of the dermis, and, for some of them, discrete interface dermatitis. In situ hybridization and immunohistochemistry were negative in all cutaneous samples. Morbilliform rash concomitant to SARS-CoV-2 infection is characterized by mild and unspecific histopathological features with no detectable viral RNA and protein and appears then not to be directly caused by the virus. Even if, at least for a few cases, the differential diagnosis with drug hypersensitivity reaction can be difficult, these cutaneous eruptions seem to rather correspond to paraviral rashes.

A comparison of DNA/RNA extraction protocols for high-throughput sequencing of microbial communities.

One goal of microbial ecology researchers is to capture the maximum amount of information from all organisms in a sample. The recent COVID-19 pandemic, caused by the RNA virus SARS-CoV-2, has highlighted a gap in traditional DNA-based protocols, including the high-throughput methods the authors previously established as field standards. To enable simultaneous SARS-CoV-2 and microbial community profiling, the authors compared the relative performance of two total nucleic acid extraction protocols with the authors' previously benchmarked protocol. The authors included a diverse panel of environmental and host-associated sample types, including body sites commonly swabbed for COVID-19 testing. Here the authors present results comparing the cost, processing time, DNA and RNA yield, microbial community composition, limit of detection and well-to-well contamination between these protocols.

Associations between COVID-19 and skin conditions identified through epidemiology and genomic studies.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is commonly associated with skin manifestations, and may also exacerbate existing skin diseases, yet the relationship between COVID-19 and skin diseases remains unclear. OBJECTIVE: By investigating this relationship through a multiomics approach, we sought to ascertain whether patients with skin conditions are more susceptible to COVID-19. METHODS: We conducted an epidemiological study and then compared gene expression across 9 different inflammatory skin conditions and severe acute respiratory syndrome coronavirus 2-infected bronchial epithelial cell lines, and then performed a genome-wide association study transdisease meta-analysis between COVID-19 susceptibility and 2 skin diseases (psoriasis and atopic dermatitis). RESULTS: Skin conditions, including psoriasis and atopic dermatitis, increase the risk of COVID-19 (odds ratio, 1.55; P = 1.4 × 10-9) but decrease the risk of mechanical ventilation (odds ratio, 0.22; P = 8.5 × 10-5). We observed significant overlap in gene expression between the infected normal bronchial epithelial cells and inflammatory skin diseases, such as psoriasis and atopic dermatitis. For genes that are commonly induced in both the severe acute respiratory syndrome coronavirus 2 infection and skin diseases, there are 4 S100 family members located in the epidermal differentiation complex, and we also identified the "IL-17 signaling pathway" (P = 4.9 × 10-77) as one of the most significantly enriched pathways. Furthermore, a shared genome-wide significant locus in the epidermal differentiation complex was identified between psoriasis and severe acute respiratory syndrome coronavirus 2 infection, with the lead marker being a significant expression quantitative trait locus for S100A12 (P = 3.3 × 10-7). CONCLUSIONS: Together our findings suggest association between inflammatory skin conditions and higher risk of COVID-19, but with less severe course, and highlight shared components involved in anti-COVID-19 immune response.

Acute Generalized Exanthematous Pustulosis (AGEP) in 12 Patients Treated for SARS-CoV-2 Positive Pneumonia.

ABSTRACT: The novel coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is rapidly spreading throughout the world. The study describes 12 patients with SARS-CoV-2 pneumonia, who developed an acute erythematous rash with nonfollicular pinhead-sized pustules, without mucosal involvement. The clinical differential diagnosis was viral rash, acute generalized exanthematous pustulosis (AGEP), or multiform erythema. computed tomography with a diagnosis of interstitial pneumonia and a respiratory tract sample positive for SARS-CoV-2 in a reverse transcriptase polymerase chain reaction assay. Patients had signs of respiratory distress and were treated with hydroxychloroquine, darunavir, ritonavir, heparin, ceftriaxone, and azithromycin. Punch biopsies showed subcorneal pustules typical of AGEP. Dermal microvascular injury and thrombosis as described in skin damage by SARS-CoV-2 infection was not observed. The direct immunofluorescence for IgG, IgA, IgM, and C3 was negative in 8 patients investigated. A polymerase chain reaction for RNA SARS-CoV-2 performed on frozen skin was negative in 5 of 6 patients. Most of our patients were treated with systemic corticosteroids. After some days (4-10), the diffuse erythema and pustules had improved. AGEP is classified as a severe cutaneous adverse reaction, provoked by drugs and acute infections. Characteristically, removal of the offending agent leads to spontaneous resolution typically in less than 15 days. The recognition of AGEP is important, in order to avoid confusion with a systemic infection and consequently to avoid incorrect treatment. Cutaneous adverse reactions to drugs are common and are major health problems worldwide causing considerable costs for health care systems. We suggest that in the patients with AGEP during SARS-CoV-2 pneumonia, viral infection is a risk factor for developing drug reaction.